Wire spring lens retainer



Dec. 23, 1958 D. P. CLAYTON ETAL 2,866,082

WIRE SPRING LENS RETAINER Filed Oct. so, 1955 z mfizWu if BY TTORNEYWIRE SPRING LENS RETAlNER David P. Clayton and Lyle N. Williams,Anderson, linrh, assignors to General Motors Corporation, Detroit, Mich,a corporation of Delaware Application October 30, 1953, Serial No.389,405

Claims. (Cl. 240-83) This invention relates to a wire spring lensretainer and more particularly to a wire spring for retaining a lenswithin a lens opening in a vehicle lamp.

It has always been difficult to mount a lens in a lamp in such manner asto insure a continued tight seal between the lens and the lamp casing.it is the practice to position a sealing gasket between the lens surfaceand the casing flange on which it is positioned in order to minimizethis problem. However, it has been found by experience that such gasketsdevelop a permanent set over a period of time thus tending to reduce thesealing pressure between the lens, gasket and body. This reduction insealing pressure makes the seal between the parts less effective. Thisdifficulty exists where the lens is made of either glass or plastic andwhere, as is the common practice in the art, the lens is retained withinthe lens aperture by means of a nut and bolt or equivalent assembly.

This problem of establishing and maintaining an adequate seal isespecially acute where a plastic lens is used in an outlook apertureprovided in the side wall of the lamp casing. In such instances, notonly is there the problem of permanent set in the sealing gasket but theuse of threaded attaching means and/or clamping elements at the ends ofthe lens tends to'spring the center portion of the lens out of theaperture and break the seal. Obviously, an assembly of this type isundesirable because of the extreme weathering conditions to which lampsof the type described are subjected in normal use.

It is therefore an object of our invention to provide a simple andinexpensive wire spring lens retainer.

It is another object of our invention to provide an improved lensretainer for insuring the continued seal between the lens and lampcasing.

It is another object of our invention to provide an improved wire springlens retainer for establishing and maintaining an effective seal betweenthe lens and the lamp casing.

To attain these objects, we provide a wire spring of generally U shape,the end portions of which bear on the lens to resiliently maintain thelens in sealing position within the lamp casing.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being bad to the accompanyingdrawing, wherein a preferred form of the present invention is clearlyshown.

In the drawing:

Figure 1 shows a front view with parts broken away of a lamp embodyingthe lens retainer of our invention.

Figure 2 is a vertical section taken on line 2-2 of the lamp shown inFigure 1.

Figure 3 is a perspective view of the wire tainer of our invention.

Referring now to the drawing and more particularly to Figure 1 there isshown a lamp 1 comprising a casing 3 having its open front end closed bya lens 5 positioned on a radially inwardly turned flange 7 formed on thefront edge of the casing. Lens 5 is retained on the casing 3 by springre- Patented Dec. 23, 1958 means of a door 9 secured to the casing byscrews 11 removably attached to brackets 13, the brackets being securedto the inner wall of the casing by any convenient means such as brazing,soldering, etc. A sealing gasket 15 is positioned between the flange 7and lens 5 in order to seal the front portion of the lamp and at thesame time not as the shock absorber therebetween. An aperture 17 isprovided in the rear wall of the casing in order to permit thepositioning of a socket assembly 19 and a light bulb 21 therein.

As is clearly shown in Figure 2, the lamp casing 3 is provided with anaperture in the bottom portion of and extending partially around theside wall in order to permit illumination of the area immediately belowthe lamp. A lens 23, either glass or plastic, is positioned in thisaperture and is commonly known as an outlook lens. A sealing gasket 25is provided between the inner wall of the casing and lens 23 in order toprovide a seal against the weathering conditions to which the lamp isnormally subjected.

Whereas it had been the accepted practice in the art to retain lens 23in its casing aperture by means of a pair of speed nuts positioned atthe ends of the lens and bearing squarely on the inner surface thereof,we provide a wire spring retainer 27 of generally U-shaped configurationadapted to bear on the end surface of the lens 23. In this manner weemploy a resilient positioning force thus compensating for any setacquired by the gasket 25 and at the same time so direct the force as tourge the lens into the aperture thus precluding the tendency to springthe center portion thereof inwardly and out of the casing aperture.

As shown on Figures 1 and 3, retainer 27 is formed with the end portions29 bent at an angle to the leg portions 31, the intermediate or baseportion 33 being bent forwardly with respect to the legs 31. The ends 34of lens 23 are notched as at 35 to provide a seat on each end edge orsurface for the end portions 29 of the retainer spring 27. The effectivelength of retainer 27 is such as to cause it to bear resiliently on theends 34 when assembled in the lamp casing, the base portion 33 reactingagainst the wall of easing 3.

In order to assemble the lamp, lens 23 is first positioned on gasket 25as shown on Figure 2. Retainer spring 27 is then positioned within thecasing in such manner that its end portions 29 are seated within thenotches 35 formed in the end surfaces 34 of the lens and the baseportion 33 projects forwardly in the casing 3 and abuts the innersurface of flange "I. it is readily apparent that the retainer 27 isthus locked in position in the casing and since its length is such thatit is stressed on being so assembled, a continued resilient force isapplied to the lens thus compensating for any permanent set taken bygasket 25. The bearing force applied to the ends 34 of lens 23 is notapplied in a plane substantially at right angles to the inner surface ofthe lens as is the present practice of the art but is instead applied atan angle more nearly tangential to the lens face to urge the centerportion of the lens into tighter position withinthe lens aperture. Itthen merely remains to assemble the light bulb 21, gasket 15, lens 5 anddoor 9 in the manner apparent on the drawing.

While we have described our invention with reference to a plasticoutlook lens, it should be understood that it is not necessarily limitedto such application. Our invention is equally as applicable to a glasslens and may be applied to a lens other than an outlook lens.

It should also be noted that the retainer spring 27 need not have itsbase portion 33 bent at an angle to the legs 31. The improved seal ofour invention may also be obtained by having the base portion in thesame plane as that of the legs and bearing on the casing wall directly1opposite the connection of the end portions 29 with the ens.

While the form of embodiment of the invention as herein disclosed,constitutes a preferred form, it is to be understood that other formsmight be adopted as may come within the scope of the claims whichfollow.

What we claim is as follows:

1. In a vehicle lamp the combination comprising a casing, a light sourcewithin said casing, an aperture in the side wall of said casing, anoutlook lens positioned said aperture on the inner wall of said casing,a resilient sealing gasket positioned between said wall and said lens,and a wire spring retainer comprising an intermediate base portionhaving divergently extending leg portions, the end of each leg portionbeing engaged with opposite end edges of said outlook lens to applyforce in a direction generally parallel to the lens surface to urge saidlens into the a erture, the base portion of said retainer being inabutting relationship with said casing, said retainer being stressedbetween said side wall and the ends of said outlook lens.

2. A vehicle lamp comprising a casing. a light source within saidcasing, an aperture in the side wall of said casing, an outlook lenspositioned in said aperture on the innerwall of said casing, a resilientsealing gasket positioned between said wall and said lens, a wire springretainer comprising an intermediate base portion having leg portionsextending therefrom. said leg portions having bent end portions engagedresiliently with opposite end edges of said outlook lens to applv forcein a direction generally parallel to the lens surface to urge said lensinto the aperture. the base ortion of said retainer being in abuttingrelationship with said casing, and a notch provided in each end of saidoutlook lens to form a seat for said retainer end ortions, said retainerbeing stressed between said side wall and the ends of said outlook lens.

3. In a vehicle lam the combination comprising a casing. a light sourcewithin said casing, an aperture in the side wall of said casing, anoutlook lens seated on the inner wall of said casing in said aperture, aresilient sealing gasket positioned between said wall and said lens, anda resilient wire retainer comprising an intermediate portion having legportions extending therefrom, the ends of the leg portions bearingagainst opposite end edges of said outlook lens to apply force in adirection generally parallel to the lens surface to urge said lens intothe aperture, the intermediate portion of said retainer being bent at anangle to the plane of the leg portions and abutting the inner surface ofsaid casing, the effective length'of said retainer being such as tonecessitate bending of the retainer on assembly in the casing.

4. A vehicle lamp comprising a casing, a lens positioned in the openfront end of said casing, a light source within said casing, an aperturein the side wall of said casing, a plastic outlook lens seated on theinner wall of said casing in said aperture, a resilient sealing gasketpositioned between said wall and said lens, a resilient wire retainercomprising an intermediate portion having leg portions extendingtherefrom, the ends of the leg portions being bent inwardly and bearingagainst the ends of said outlook lens, the intermediate portion of saidretainer being bent at an angle to the plane of the leg portions andabutting the inner surface of said casing, and a notch formed in eachend of said outlook lens to provide a seat for said retainer ends, theeffective length of said retainer being such as to require bending ofthe intermediate portion relative to its leg portions on assembly in thecasing.

5. A vehicle lamp comprising a casing having a flange formed on its openfront end, a lens positioned in the open front end of said casing, alight source within said casing, an aperture in the side wall of saidcasing, a plastic outlook lens seated on the inner wall of said casingin said aperture, a resilient sealing gasket positioned between saidwall and said lens, a resilient wire retainer comprising an intermediateportion having leg portions extending therefrom, the ends of the legportions being bent inwardly and bearing against the ends of saidoutlook lens, the intermediate portion of said retainer being bent at anangle to the plane of the leg portions and abutting the inner surface ofsaid flange, and a notch formed in each end of said outlook lens toprovide a seat for said retainer ends, the effective length of saidretainer being such as to require bending of the intermediate portionrelative to its leg portions on assembly in the casing.

References Cited in the file of this patent UNITED STATES PATENTS945,049 Russell Ian. 4, 1910 1,110,910 Elliot Sept. 15, 1914 1,677,074Corcoran July 10, 1928 1,685,575 Springer Sept. 25, 1928 1,974,341Middleton Sept. 18, 1934 2,616,029 Osowki Oct. 28, 1952 2,616,030 VanDyke Oct. 28, 1952 2,686,867 Lewellen et al Aug. 17, 1954 2,733,336Clayton Jan. 31, 1956

